As of September 13th, there have been 11 days so far this year reaching 90 degrees or higher in Cincinnati, 17 in Columbus, and 15 in Dayton.
Based on the 30-year climatological normal period 1981 to 2010, there are on average 21 days each year reaching 90 degrees
or higher in Cincinnati, 18 in Columbus, and 14 in Dayton.

Below are graphs showing the annual frequency of days
in the 90s for each of our three climate stations, beginning with the first full year of data on record for each site. Click
each graph for a larger version. Click here for the full dataset.